An Empirical Approach to Derive Water T from Multiparametric MR Images Using an Automated Pipeline and Comparison With Liver Stiffness.

Background: Water T of the liver has been shown to be promising in discriminating the progressive forms of fatty liver diseases, inflammation, and fibrosis, yet proper correction for iron and lipid is required.

Purpose: To examine the feasibility of an empirical approach for iron and lipid correction when measuring imaging-based T and to validate this approach by spectroscopy on in vivo data.

Study Type: Retrospective.

Intramyocellular Triglyceride Content During the Early Course of Type 1 and Type 2 Diabetes.

Unlabelled: Intramyocellular lipid content (IMCL) is elevated in insulin-resistant humans, but it changes over time, and relationships with comorbidities remain unclear. We examined IMCL during the initial course of diabetes and its associations with complications. Participants of the German Diabetes Study (GDS) with recent-onset type 1 (n = 132) or type 2 diabetes (n = 139) and glucose-tolerant control subjects (n = 128) underwent 1H-MRS to measure IMCL and muscle volume, whole-body insulin sensitivity (hyperinsulinemic-euglycemic clamps; M-value), and cycling spiroergometry (VO2max).

Multiparametric Longitudinal Profiling of RCAS-tva-Induced PDGFB-Driven Experimental Glioma.

Glioblastomas are incurable primary brain tumors harboring a heterogeneous landscape of genetic and metabolic alterations. Longitudinal imaging by MRI and [F]FET-PET measurements enable us to visualize the features of evolving tumors in a dynamic manner. Yet, close-meshed longitudinal imaging time points for characterizing temporal and spatial metabolic alterations during tumor evolution in patients is not feasible because patients usually present with already established tumors.

PET/MRI enables simultaneous quantification of β-cell mass and function.

Non-invasive imaging of β-cells represents a desirable preclinical and clinical tool to monitor the change of β-cell mass and the loss of function during pre-diabetic stages. Although it is widely accepted that manganese (Mn) ions are actively gated by voltage-dependent calcium channels (VDCC) in response to glucose metabolism, little is known on its specificity for quantification of islet β-cell function using Mn and magnetic resonance imaging (MRI). On the other hand, glucagon-like-peptide-1 receptor (GLP-1R) represents a validated target for the estimation of β-cell mass using radiolabeled exendin-4 (Ex4) and positron emission tomography (PET).

Noninvasive evaluation of renal pH homeostasis after ischemia reperfusion injury by CEST-MRI.

Acute kidney injury (AKI) in mice caused by sustained ischemia followed by reperfusion is associated with acute tubular necrosis and renal dysfunctional blood flow. Although the principal role of the kidney is the maintenance of acid-base balance, current imaging approaches are unable to assess this important parameter, and clinical biomarkers are not robust enough in evaluating the severity of kidney damage. Therefore, novel noninvasive imaging approaches are needed to assess the acid-base homeostasis in vivo.

In Vitro and In Vivo Assessment of Nonionic Iodinated Radiographic Molecules as Chemical Exchange Saturation Transfer Magnetic Resonance Imaging Tumor Perfusion Agents.

Objectives: The aim of this study was to evaluate 4 nonionic x-ray iodinated contrast agents (CAs), commonly used in radiographic procedures, as novel chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) agents by assessing their in vitro exchange properties and preliminary in vivo use as tumor enhancing agents.

Materials And Methods: The CEST properties, as function of pH (range, 5.5-7.

A general MRI-CEST ratiometric approach for pH imaging: demonstration of in vivo pH mapping with iobitridol.

Chemical exchange saturation transfer (CEST) is a novel contrast mechanism for magnetic resonance imaging (MRI). CEST MRI selectively saturates exchangeable protons that are transferred to MRI-detectable bulk water signal. MRI-CEST (pH)-responsive agents are probes able to map pH in the microenvironment in which they distribute.